Golf club head

ABSTRACT

A cavity back iron type golf club head includes a face portion, a back portion, and at least one reinforcing portion that extends from an upper edge portion of the back portion toward a toe-side portion of a top line.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority to and the benefit of Japanese PatentApplication No. 2019-117043 filed on Jun. 25, 2019, the entiredisclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a cavity back iron type golf club head.

Description of the Related Art

As a method for improving the performance of the face portion of a golfclub head, Japanese Patent Laid-Open No. 2012-071111 discloses a golfclub head in which a portion larger in mass than the surroundings isprovided at a part that becomes the antinode of the vibration of theface portion. Japanese Patent No. 6095348 discloses a golf club head inwhich a plurality of grooves are formed in a part of the back surface ofthe face portion. Japanese Patent Laid-Open No. 10-248970 discloses agolf club head in which the flexural rigidity in the vibration part onthe toe side is increased. Japanese Patent No. 5156994 discloses a golfclub head in which a reinforcing portion is provided at the position ofthe node of the vibration at the time of striking a ball. JapanesePatent Laid-Open No. 11-347161 discloses a golf club head whose naturalfrequency is confined to fall within a specific range.

In general, an iron type golf club head includes a hosel portion on theheel side and a thick sole portion, so that the toe side of the faceportion tends to easily vibrate. As one form of an iron type golf clubhead, a cavity back iron type golf club head is known. However, the golfclub head of this type includes a face portion formed to be relativelythin, so that in some cases, the vibration on the toe side of the faceportion becomes larger at the time of striking a ball. This vibrationmay deteriorate a shot feeling.

SUMMARY OF THE INVENTION

It is an object of the present invention to improve a shot feeling of acavity back iron type golf club head.

According to an aspect of the present invention, there is provided acavity back iron type golf club head comprising: a face portion; a backportion; and at least one reinforcing portion that extends from an upperedge portion of the back portion toward a toe-side portion of a topline.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments (with reference to theattached drawings).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a front view of a golf club head according to an embodiment;

FIG. 1B is a back view of the golf club head according to theembodiment;

FIG. 2A is a sectional view taken along a line A-A in FIG. 1B;

FIG. 2B is a perspective view of the golf club head;

FIG. 3A is a sectional view taken along a line B-B in FIG. 1B;

FIG. 3B is a view showing another example of the sectional shape of areinforcing portion;

FIG. 4 is a view showing another arrangement example of the reinforcingportion;

FIG. 5A is a view showing still another arrangement example of thereinforcing portion; and

FIG. 5B is a view showing still another arrangement example of thereinforcing portion.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, embodiments will be described in detail with reference tothe attached drawings. Note that the following embodiments are notintended to limit the scope of the claimed invention, and limitation isnot made an invention that requires all combinations of featuresdescribed in the embodiments. Two or more of the multiple featuresdescribed in the embodiments may be combined as appropriate.Furthermore, the same reference numerals are given to the same orsimilar configurations, and redundant description thereof is omitted.

First Embodiment

With reference to FIGS. 1A to 3A, a golf club head 1 according to anembodiment of the present invention will be described. FIG. 1A is afront view of the golf club head 1, and FIG. 1B is a back view thereof.FIG. 2A is a sectional view taken along a line A-A in FIG. 1B, FIG. 2Bis a perspective view of the golf club head 1 viewed from a toe side,and FIG. 3A is a sectional view taken along a line B-B in FIG. 1B. Inthe drawings, an arrow D1 indicates a toe-heel direction, and an arrowD2 indicates a height direction of the face portion. The heightdirection is a vertical direction parallel to the surface of a faceportion 4 in a state in which the golf club head 1 is in contact withthe ground in accordance with a predetermined lie angle and apredetermined loft angle.

The golf club head 1 is a cavity back iron type golf club head. Thepresent invention is applicable to any of a long iron, a middle iron, ashort iron, and a wedge.

The golf club head 1 includes a top line 2 forming the head top portion,a sole portion 3 forming the head bottom portion, the face portion 4, ahosel portion 5, a back portion 6, and a toe-side side portion 8. Thehosel portion 5 has a cylindrical shape into which a shaft (not shown)is inserted.

The face portion 4 forms a golf ball striking surface. In thisembodiment, the face portion 4 forms a flat striking surface, and aplurality of score lines 4 a extending in the D1 direction are formed inthe D2 direction. A chain line FC indicates the center line (facecenter) of the face portion 4 in the D1 direction. A back surface 4 b ofthe face portion 4 is a surface opposite to the striking surface, and apart of the back surface 4 b is exposed when viewed from the backsurface of the golf club head 1.

The back portion 6 forms a rear portion (back portion) of the head, andparticularly forms a rear portion at a lower portion of the head. Anupper edge portion 6 a of the back portion 6 extends in the D1direction, and a step S is formed in the midway portion of the upperedge portion 6 a. Note that a structure including no step S can also beemployed. The golf club head 1 of this embodiment is a pocket cavitytype head, in which a concave portion is formed between the back portion6 and the rear portion of the top line 2, and a slit-shaped pocket P isformed between the lower portion of the back surface 4 b of the faceportion 4 and the back portion 6. The pocket P extends in the D1direction. Note that the pocket cavity type head is exemplified in thisembodiment, but the present invention is also applicable to a cavityback iron type head including no pocket (with the pocket P filled).

Here, in general, an iron type golf club head includes a hosel portionhaving a rigid structure on the heel side, and the sole width is thickeron the heel side than on the top side. Accordingly, the rigidity is highon the heel side, and low on the toe side and the top line side.Accordingly, in some cases, the vibration on the toe side of the faceportion becomes larger at the time of striking a ball. Particularly, ina cavity back iron type head like the golf club head 1 of thisembodiment, the face portion 4 is formed to be relatively thin, so thatthe vibration on the toe side of the face portion 4 becomes larger atthe time of striking a ball. Further, as in this embodiment, in a pocketcavity type iron head, the face portion 4 easily deforms due to thepresence of the pocket P, so that the face portion 4 on the toe-side andtop line-side easily vibrates. This vibration may deteriorate a shotfeeling.

Therefore, a reinforcing portion 7 is provided in this embodiment. Thereinforcing portion 7 extends from the upper edge portion 6 a of theback portion 6 toward the toe-side portion of the top line 2. Byconnecting the toe-side portion of the top line 2 to the back portion 6via the reinforcing portion 7, the rigidity of the face portion 4 on thetoe side and top line side can be increased. As a result, it is possibleto suppress generation of the vibration that deteriorates a shot feelingat the time of striking a ball. The reinforcing portion 7 extends so asto cross above the pocket P, so the deformation performance of the faceportion 4 due to the presence of the pocket P is not significantlyimpaired.

The reinforcing portion 7 of this embodiment is a long bar member havinga rectangular cross-sectional shape in a direction intersecting itsextending direction as shown in FIG. 3A, and includes a lower endportion 7 a, an upper end portion 7 b, and an intermediate portion 7 ctherebetween. Note that the cross-sectional shape of the reinforcingportion 7 may be other than the rectangle shown in FIG. 3A, and may be,for example, a C-shape (concave shape) open toward the face portion 4 asshown in FIG. 3B. This can achieve the weight reduction of thereinforcing portion 7 and the lower center of gravity of the head. Inorder to improve the rigidity, a width W in a direction intersecting theextending direction of the reinforcing portion 7 is, for example, 3 mmto 12 mm (both inclusive).

The end portion 7 a is integrally connected to the step S of the upperedge portion 6 a of the back portion 6. The end portion 7 b isintegrally connected to the toe-side portion of the top line 2.Particularly, in this embodiment, the end portion 7 b is connected tothe corner portion between the top line 2 and the side portion 8, sothat the rigidity of the face portion 4 can be further increased on thetoe side and top line side.

The intermediate portion 7 c is separated from the back surface 4 b ofthe face portion 4, and the reinforcing portion 7 forms a bridge betweenthe upper edge portion 6 a of the back portion 6 and the toe-sideportion of the top line 2. Since the intermediate portion 7 c isseparated from the back surface 4 b of the face portion 4, thedeformation of the face portion 4 at the time of striking a ball can beprevented from being unnecessarily constrained. In addition, arrangingthe intermediate portion 7 c at a position away from the back surface 4b of the face portion 4 means arranging a heavy object at a positionaway from the face portion 4, so that the center of gravity of the headcan be set at a position deeper from the face portion 4. Note that inorder to improve the rigidity of the face portion 4, a structure inwhich the intermediate portion 7 c is in contact with the back surface 4b or a structure in which the intermediate portion 7 c is integrallyconnected to the back surface 4 b can also be employed.

The reinforcing portion 7 as a whole is arranged closer to the toe sidethan the face center (FC) in the D1 direction. This can increase therigidity of the face portion 4 on the toe side. In addition, in thereinforcing portion 7, the end portion 7 a is located closer to the heelside than the end portion 7 b in the D1 direction. This can increase therigidity of the face portion 4 on the toe side and upper side.

Second Embodiment

An arrangement example in which the width W is constant in the extendingdirection of the reinforcing portion 7 has been described in the firstembodiment, but the width W may not be constant. FIG. 4 shows an exampleof this case. In the illustrated example, a width W1 of an end portion 7a is larger than a width W2 of an end portion 7 b, and the widthgradually decreases from the end portion 7 a toward the end portion 7 b(from an upper edge portion 6 a toward the toe-side portion of a topline 2). Thus, the rigidity of the toe-side portion of the top line 2can be improved while lowering the center of gravity of the head.

Third Embodiment

In the first embodiment, the structure in which the reinforcing portion7 is integrally formed with the remaining portion of the golf club head1 has been assumed. However, the reinforcing portion 7 may be formed bya member different from the remaining portion of the golf club head 1.FIG. 5A shows an example of this case. In the illustrated example, areinforcing portion 7 is formed by a reinforcing member 7A. In thereinforcing member 7A, an end portion 7 a is fixed to a back portion 6by a screw 9, and an end portion 7 b is fixed to a top line 2 by anotherscrew 9. A through hole into which the screw 9 is inserted is formed ineach of the end portions 7 a and 7 b, and a screw hole with which thescrew 9 is screwed is formed in each of the back portion 6 and the topline 2. In this embodiment, the reinforcing member 7A is fixed by thescrews 9, but another mechanical fixing structure such as caulking orpress-fitting may be used.

By forming the reinforcing portion 7 by the reinforcing member 7A thatis a separate member, a golf club head 1 may be easily manufactured. Inaddition, since it becomes possible to make the reinforcing portion 7replaceable, a golfer may be allowed to select one reinforcing member 7Afrom a plurality of types of reinforcing members 7A having differentphysical characteristics such as rigidity, elasticity, mass, or aspecific gravity.

In addition, by forming the reinforcing portion 7 as the separatemember, the remaining portion of the golf club head 1 and thereinforcing portion 7 can be made of different materials. Examples ofthe material of the reinforcing portion 7 (reinforcing member 7A) caninclude soft iron, stainless steel, titanium, an aluminum alloy, and atungsten alloy. Examples of the material of the remaining portion of thegolf club head 1 can include soft iron, stainless steel, copper,titanium, and an aluminum alloy. The reinforcing portion 7 (reinforcingmember 7A) may be a member having a higher specific gravity than theremaining portion of the golf club head 1. The large specific gravity ofthe reinforcing portion 7 can achieve the deeper center of gravity.

In addition to forming the golf club head 1 by two members, thereinforcing portion 7 and the remaining portion, the golf club head 1may be formed by three members in total in which the remaining portionis formed by two members, a face member forming a face portion 4 and amain body member forming portions (for example, a sole portion 3, ahosel portion 5, a back portion 6, and a side portion 8) other than theface portion 4. Further, the golf club head 1 may be formed by twomembers, the face member forming the face portion 4 and the main bodymember forming the remaining portion including the reinforcing portion7.

Fourth Embodiment

In the first embodiment, one reinforcing portion 7 is provided. However,a plurality of reinforcing portions 7 may be provided. FIG. 5B shows anexample of this case. In the illustrated example, two reinforcingportions 7B and 7C are provided. The plurality of reinforcing portions7B and 7C can increase the rigidity of the face portion 4 on the toeside and upper side. In order to improve the rigidity, the width (widthWin FIG. 1B) of each of the reinforcing portions 7B and 7C is, forexample, 3 mm to 10 mm (both inclusive).

Each of the reinforcing portions 7B and 7C as a whole is arranged closerto the toe side than the face center (FC) in a D1 direction, and an endportion 7 a is located closer to the heel side than an end portion 7 bin the D1 direction. However, for example, a structure in which the endportion 7 a of the reinforcing portion 7C is located closer to the heelside than the face center (FC) in the D1 direction can also be employed.

In this embodiment, the reinforcing portions 7B and 7C extend inparallel with each other, but they may intersect with each other, or maynot intersect but be in non-parallel.

The invention is not limited to the foregoing embodiments, and variousvariations/changes are possible within the spirit of the invention.

What is claimed is:
 1. A cavity back iron type golf club headcomprising: a face portion; a back portion; and at least one reinforcingportion that extends from an upper edge portion of the back portiontoward a toe-side portion of a top line.
 2. The golf club head accordingto claim 1, wherein the golf club head is a pocket cavity iron type golfclub head in which a pocket is formed between a lower portion of a backsurface of the face portion and the back portion, and the reinforcingportion extends so as to cross above the pocket.
 3. The golf club headaccording to claim 1, wherein the reinforcing portion is formed by amember different from a remaining portion of the golf club head, and oneend portion of the different member is fixed to the upper edge portion,and the other end portion of the different member is fixed to thetoe-side portion.
 4. The golf club head according to claim 1, comprisinga plurality of the reinforcing portions, wherein a width of thereinforcing portion in a direction intersecting an extending directionof the reinforcing portion is not less than 3 mm and not more than 10mm.
 5. The golf club head according to claim 3, wherein the differentmember is a member of a material different from a material forming theback portion and the top line.
 6. The golf club head according to claim3, wherein the different member is a member of at least one of softiron, stainless steel, titanium, and an aluminum alloy.
 7. The golf clubhead according to claim 3, wherein the different member is a memberhaving a higher specific gravity than a material forming the backportion and the top line.
 8. The golf club head according to claim 1,wherein an intermediate portion of the reinforcing portion in anextending direction of the reinforcing portion is separated from a backsurface of the face portion.
 9. The golf club head according to claim 1,wherein a width of the reinforcing portion in a direction intersectingan extending direction of the reinforcing portion gradually decreasesfrom the upper edge portion toward the toe-side portion.
 10. The golfclub head according to claim 1, wherein a cross-sectional shape of thereinforcing portion in a direction intersecting an extending directionof the reinforcing portion is a C-shape open toward the face portion.